Light-absorbing filters

ABSTRACT

light-absorbing filters comprise a self-supporting polymeric film, such as an oriented polyethylene terephthalate film, containing or coated with a lacquer containing a compound which absorbs light in the wavelength band less than 0.4 μm (i.e. UV light). The filters are particularly useful as UV-absorbing filters for use in flashbulbs for color photography. Suitable light-absorbing compounds are hydroxyphenyl benzotriazoles, e.g. 2(2&#39;-hydroxy-3&#39;,5&#39;-di-t-amylphenyl)benzotriazole, and hydroxy-substituted benzophenone, e.g. 2,2&#39;-dihydroxy-4,4&#39;-dimethoxy-benzophenone.



